Oil and gas wells produce oil, gas, and/or by-products from underground reservoirs. Oil and gas reservoirs are formations of rock containing oil and/or gas. The type and properties of the rock may vary by reservoir and also within reservoirs. For example, the porosity and permeability of a reservoir rock may vary from reservoir to reservoir and from well to well in a reservoir. The porosity is the percentage of core volume, or void space, within the reservoir rock that can contain fluids. The permeability is an estimate of the reservoir rock's ability to flow or transmit fluids. A reservoir may include a plurality of reservoir zones, and the zones may have properties different from each other, and the properties within a zone may vary. Further, different reservoir zones may be formed from different types of rock.
Oil and gas production from a well may be stimulated by fracture, acid or other production enhancement treatment. In a fracture treatment, fluids are pumped downhole under high pressure to artificially fracture the reservoir rock in order to increase permeability and production. In some implementations, a pad, which is fracture fluids without proppants, is first pumped down the well until formation breakdown. Then, the fracturing fluid with proppants is pumped downhole to hold the fractures open after pumping stops. At the end of the fracture treatment, a clear fluid flush may be pumped down the well to flush the well of proppants.
In some instances, an initial treatment or minifracture may be performed before a production stimulation fracture treatment to calculate formation and fracture properties. In some implementations, the initial treatment may be an injection falloff test.